Cobalt-substituted aluminophosphate molecular sieves: x-ray absorption, infrared spectroscopic, and catalytic studies

1992 ◽  
Vol 4 (6) ◽  
pp. 1373-1380 ◽  
Author(s):  
Jiesheng Chen ◽  
Gopinathan Sankar ◽  
John Meurig Thomas ◽  
Ruren Xu ◽  
G. Neville Greaves ◽  
...  
Keyword(s):  
Molecular Sieves ◽  
X Ray ◽  
Aluminophosphate Molecular Sieves ◽  
Infrared Spectroscopic ◽  
X Ray Absorption

ChemInform Abstract: Cobalt-Substituted Aluminophosphate Molecular Sieves: X-Ray Absorption, IR Spectroscopic, and Catalytic Studies.

ChemInform ◽  
2010 ◽  
Vol 24 (9) ◽  
pp. no-no
Author(s):  
J. CHEN ◽  
G. SANKAR ◽  
J. M. THOMAS ◽  
R. XU ◽  
G. N. GREAVES ◽  
...  
Keyword(s):  
Molecular Sieves ◽  
X Ray ◽  
Aluminophosphate Molecular Sieves ◽  
Ir Spectroscopic ◽  
X Ray Absorption

scholarly journals Identifying the location of Cu ions in nanostructured SAPO-5 molecular sieves and its impact on the redox properties

RSC Advances ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 6429-6437
Author(s):  
Jörg Radnik ◽  
Thi Thuy Hanh Dang ◽  
Suresh Gatla ◽  
Vikram Singh Raghuwanshi ◽  
Dragomir Tatchev ◽  
...  
Keyword(s):  
Small Angle ◽  
Molecular Sieves ◽  
Redox Properties ◽  
X Ray ◽  
Absorption Fine ◽  
X Ray Scattering ◽  
X Ray Absorption ◽  
Cu Ions ◽  
Ray Scattering

Where is the Cu located? Combining X-ray Absorption Fine Spectroscopy (XAFS) with Anomalous Small-Angle X-ray Scattering (ASAXS) can answer this question for Cu loaded molecular sieves.

X-ray absorption spectroscopy of Ti-containing molecular sieves ETS-10, aluminum-free Ti-β, and TS-1

1995 ◽  
Vol 34 (1-2) ◽  
pp. 101-113 ◽  
Author(s):  
R. J. Davis ◽  
Z. Liu ◽  
J. E. Tabora ◽  
W. S. Wieland
Keyword(s):  
Absorption Spectroscopy ◽  
Molecular Sieves ◽  
X Ray ◽  
X Ray Absorption

X-ray microanalysis of thin specimens in the transmission electron microscope at voltages up to 1000 Kv.

1978 ◽  
Vol 36 (1) ◽  
pp. 540-541
Author(s):  
G. Cliff ◽  
M.J. Nasir ◽  
G.W. Lorimer ◽  
N. Ridley
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Weight Fraction ◽  
Present Series ◽  
Constant Independent ◽  
X Ray ◽  
Transmission Electron ◽  
Series Of Experiments ◽  
Image Position ◽  
X Ray Absorption

In a specimen which is transmission thin to 100 kV electrons - a sample in which X-ray absorption is so insignificant that it can be neglected and where fluorescence effects can generally be ignored (1,2) - a ratio of characteristic X-ray intensities, I1/I2 can be converted into a weight fraction ratio, C1/C2, using the equationwhere k12 is, at a given voltage, a constant independent of composition or thickness, k12 values can be determined experimentally from thin standards (3) or calculated (4,6). Both experimental and calculated k12 values have been obtained for K(11<Z>19),kα(Z>19) and some Lα radiation (3,6) at 100 kV. The object of the present series of experiments was to experimentally determine k12 values at voltages between 200 and 1000 kV and to compare these with calculated values.The experiments were carried out on an AEI-EM7 HVEM fitted with an energy dispersive X-ray detector.

SIGMAL: A Program for Calculating L-Shell lonization Cross-Sections

1981 ◽  
Vol 39 ◽  
pp. 198-199 ◽  
Author(s):  
R.F. Egerton
Keyword(s):  
Cross Sections ◽  
Fortran Program ◽  
Absorption Data ◽  
X Ray ◽  
Atomic Electrons ◽  
Energy Dependent ◽  
Hydrogenic Model ◽  
Electron Energy Loss ◽  
X Ray Absorption ◽  
Shell Ionization

SIGMAL is a short (∼ 100-line) Fortran program designed to rapidly compute cross-sections for L-shell ionization, particularly the partial crosssections required in quantitative electron energy-loss microanalysis. The program is based on a hydrogenic model, the L1 and L23 subshells being represented by scaled Coulombic wave functions, which allows the generalized oscillator strength (GOS) to be expressed analytically. In this basic form, the model predicts too large a cross-section at energies near to the ionization edge (see Fig. 1), due mainly to the fact that the screening effect of the atomic electrons is assumed constant over the L-shell region. This can be remedied by applying an energy-dependent correction to the GOS or to the effective nuclear charge, resulting in much closer agreement with experimental X-ray absorption data and with more sophisticated calculations (see Fig. 1 ).

point-Analysis Using the Extrapolation Method in the Analytical Electron microscope

1990 ◽  
Vol 48 (2) ◽  
pp. 430-431
Author(s):  
Zenji Horita ◽  
Ryuzo Nishimachi ◽  
Takeshi Sano ◽  
Minoru Nemoto
Keyword(s):  
Electron Microscope ◽  
Extrapolation Method ◽  
X Ray ◽  
Absorption Correction ◽  
Point Analysis ◽  
Analytical Electron ◽  
Analytical Electron Microscope ◽  
Data Points ◽  
Identical Composition ◽  
X Ray Absorption

Absorption correction is often required in quantitative x-ray microanalysis of thin specimens using the analytical electron microscope. For such correction, it is convenient to use the extrapolation method[l] because the thickness, density and mass absorption coefficient are not necessary in the method. The characteristic x-ray intensities measured for the analysis are only requirement for the absorption correction. However, to achieve extrapolation, it is imperative to obtain data points more than two at different thicknesses in the identical composition. Thus, the method encounters difficulty in analyzing a region equivalent to beam size or the specimen with uniform thickness. The purpose of this study is to modify the method so that extrapolation becomes feasible in such limited conditions. Applicability of the new form is examined by using a standard sample and then it is applied to quantification of phases in a Ni-Al-W ternary alloy.The earlier equation for the extrapolation method was formulated based on the facts that the magnitude of x-ray absorption increases with increasing thickness and that the intensity of a characteristic x-ray exhibiting negligible absorption in the specimen is used as a measure of thickness.

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